Revealed regarding badri sahabas..
وَلاَ تَقُولُواْ لِمَن يُقْتَلُ فِى سَبيلِ اللَّهِ أَمْوَاتٌ بَلْ أَحْيَاءٌ وَلَكِن لاَّ تَشْعُرُونَ
And say not of those who are killed in the way of Allah, “They are dead.” Nay, they are living, but you perceive (it) not.
[Surah Baqarah V154]
This verse was revealed regarding sahaba رضي الله عنهم martyred at Battle of Badr.